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1.
基于PSR模型的三峡水库消落带生态环境综合评价   总被引:1,自引:0,他引:1  
基于压力-状态-响应(Pressure-State-Response,PSR)模型构建三峡水库消落带生态环境综合评价指标体系,结合遥感影像解译与调研数据,应用层次分析法对三峡水库消落带的生态环境综合状况进行评价,度量消落带生态环境综合状况指数(Comprehensive Situation Index,CSI);基于ANOVA分析方法阐述CSI对于河流区段的响应.结果表明,三峡水库消落带总体生态环境综合评价指数为0.47,处于一般等级,三峡水库消落带各区域的生态环境综合指数分布在0.37~0.65范围内,83.3%的区域消落带生态环境综合状况等级为一般;不同区段间消落带生态环境状况存在显著差异(P<0.05),为上游段>中游段>下游段.  相似文献   

2.
南海北部生物多样性保护现状与研究进展   总被引:4,自引:0,他引:4  
为了有序利用和合理保护南海丰富的生物多样性资源,根据近年最新研究成果,并结合以往调查资料,对南海北部生物多样性保护和研究进展进行了综述。重点阐述了南海北部海洋生物的遗传多样性、物种多样性和生态系统多样性状况、保护现状及其研究进展,分析了目前海洋生物多样性保护所面临的主要威胁,探讨了生物多样性的主要保护对策。  相似文献   

3.
在海洋牧场生态系统特征及健康内涵的基础上,针对海洋牧场区域这一复杂的生态系统,基于压力-状态-响应(PSR)模型,结合海洋牧场生态系统特征和所收集的数据特点及其可获取性等,经过反复筛选与提炼,形成由压力、状态和响应共33个具体评价指标组成的海洋牧场生态系统健康评价指标体系及具体指标,并对指标的选取和体系构建的构建进行了简要的诠释,通过熵权法对各指标进行权重计算,为了定量海洋牧场生态系统健康状态,通过建立综合健康指数,确定海洋牧场生态系统的健康状态。  相似文献   

4.
为探究常州段底栖动物的多样性状况和变化趋势,进一步开展河道生态监测与水质评价,通过连续多年对京杭运河常州老运河段底栖动物的调查,分析其群落结构分布特征和变化规律,采用Shannon-Wiener指数、BI指数对河段的底栖动物多样性进行评价,并利用污染生物效应指数(BPI)对水质进行评价。结果表明,常州段上游的底栖动物种类最多、种群丰富度最高、群落完整性最好、多样性状况最好、生态污染效应最小,中游次之,下游最差,底栖动物多样性正逐年得到恢复;2009-2013年,常州段的污染生物效应指数逐年上升,污染效应逐年下降,污染程度逐年减轻,由此说明该河段的水质正逐年得到改善,生态环境逐步好转。  相似文献   

5.
海洋生物多样性研究进展及其热点分析   总被引:1,自引:0,他引:1  
在全球气候变化和人类活动的干扰下,海洋生物多样性及其可持续利用受到了严重威胁,对海洋生物多样性的研究也逐渐成为各国学者当前的研究热点。基于Web of Science核心合集的文献数据,利用文献计量学和知识图谱方法,对其发文量的增长趋势、来源期刊和区域分布以及学科类别等进行分析,并基于合作网络、关键词共现的知识图谱及突变检测等方法,探究全球海洋生物多样性的研究进展及其热点。结果显示,研究文献的年度发文量总体上呈动态递增趋势,且文献的科研影响力及国际关注度非常高;发文量较多的作者、机构间均形成了密切而稳定的合作关系,Miloslavich P、Danovaro R和Mouillot D等为该领域的核心作者,以詹姆斯库克大学、塔斯马尼亚大学及不列颠哥伦比亚大学等机构为核心的机构间建立了广泛的合作关系,主要涉及的学科类别为生态学、生物多样性保护、海洋淡水生物学及环境科学等。当前,全球海洋生物多样性的研究热点主要有5个方向:(1)人类活动和气候变化对海洋生物多样性的影响;(2)海洋生物多样性保护及其可持续利用;(3)国家管辖范围外海洋保护区及具有重要生态或生物学意义的海域生物多样性研究;(4)海洋生物多样性和生态系统变化的观测及其评价;(5)海洋遗传多样性和海洋生物多样性的地理变异研究。  相似文献   

6.
海湾生境状况评价是科学客观认知海湾环境及其栖息生物的状态以及揭示时空演变趋势的评估方法。综合考虑渤海湾生境现状、压力和影响因素等,建立指标体系;结合中尺度区域(渤海)的数据分析结果,给出评估区域(渤海湾)的指标临界值并建立定量评价模式,评估判断渤海湾生境状况的时空特征与演变趋势。结果显示:水质状况为一般,趋势为向好变化;沉积物生态风险指标为优秀状况,向好趋势,重金属RI和E_r^i趋势均表现为明显降低;浮游植物、底栖生物的物种多样性指数评价结果均为一般状况,从趋势来看浮游植物的变化为向差趋势,底栖生物为向好趋势;鸟类数量和种类近年来增长,指标评价为良好状况,向好趋势;渤海渔业资源持续恶化,指标状况为较差;潮间带湿地退化率超过60%,栖息地退化严重,状况为恶劣;自然岸线急剧减少且破碎化严重,岸线利用呈持续高强度,指标状况为一般,变差趋势。  相似文献   

7.
基于压力、状态、响应模型(PSR)和层次分析法(AHP),确定17项指标通过数据的标准化处理,指标权重赋值、权重一致性检验、评价等级确定以及评价模型的构建,用生态安全评价黄河陕西段鱼类增殖放流效果,分析生态安全所面临的主要问题。结果表明:黄河陕西段2013年增殖放流生态安全度(ESI)评价等级为Ⅱ级,为良好状态;2014年评价等级为Ⅲ级,处于一般状态;2015年评价等级为Ⅳ级,处于较差状态,属于临界不安全状态以下水平。生态安全形势呈现出逐年下降局势。不安全状态受到影响较大的前3个指标是:黄河径流量变化影响、重要生境保持率和公众资源环境保护意识的影响,3个指标下降值占到下降ESI值的64.93%。其次还受到污水排放达标率、鱼类增殖放流量、政策和管理水平、鱼类生物多样性指数、保护区建设、水质综合污染指数、群落结构等诸多因素影响。研究显示,现阶段增殖放流对黄河生态安全有一定影响,还存在一定提升空间。  相似文献   

8.
为了解库区建设对鱼类生物多样性的影响,掌握董箐库区内渔业资源群落组成和物种多样性变化情况。2013年--2015年在董箐库区进行6次生物采样和走访调查,采集渔获物共668尾,隶属3目8科29属39种,鲤科鱼类最多,占总数的60.8%;群落以杂食性鱼类和喜静缓流生态类型鱼类为主,唇鲮(Semilabeo notabilis)、花鱼骨(Hemibarbus maculatus)、鲤鱼(Cyprinus carpio)、鲫鱼(Carassius auratus)、云南光唇鱼(Acrossocheilus yunnanensis)、光倒刺鲃(S.hollandi)、黄颡鱼(Pelteobagrus fulvidracoi)为库区的优势种,对比历史资料发现库区鱼类群落结构已发生改变;董箐库区鱼类群落生物多样性采用Margalef 丰富度指数、Shannon-wiener多样性指数()、Pielou均匀度指数()、Wilhm改进指数()作为评价指标,各指标的平均值为3.811、0.914、2.649、2.529,分析数据发现鱼类生物多样性也有衰减。  相似文献   

9.
丹江口库区生态环境问题是南水北调工程建设和运营中关注的热点,生物多样性是生态环境的重要组成部分以及主要评价指标.本文通过资料收集和对库区野外调查,对丹江口库区野生植物、陆生动物和水生生物三个方面进行了生物多样性资源统计,重点从大坝加高蓄水淹没、移民安置破坏两方面分析了南水北调中线工程可能对库区生物多样性造成的影响,并根据目前库区生物多样性的现状以及面临的威胁,提出了生物多样性保护措施.  相似文献   

10.
北盘江董箐水电站库区鱼类资源调查   总被引:1,自引:0,他引:1  
为探究董箐水电站成库后库区内渔业资源群落组成和物种多样性变化情况,给董箐水库资源的合理开发与利用、库区鱼类资源保护以及增殖放流活动提供技术参考和科学依据,于2013-2015年在董箐库区进行6次生物采样和走访调查。结果表明,本次调查共采集渔获物668尾,隶属3目、8科、29属、39种,其中鲤科鱼类最多,占总种类数的60.8%;唇鲮(Semilabeo notabilis)、花鱼骨(Hemibarbus maculatus)、鲤(Cyprinus carpio)、鲫(Carassius auratus)、云南光唇鱼(Acrossocheilus yunnanensis)、光倒刺鲃(Spinibarbus hollandi)、黄颡鱼(Pelteobagrus fulvidracoi)为库区的优势种;董箐库区鱼类群落生物多样性采用Margalef丰富度指数(DMa)、Shannon-Wiener多样性指数(H')和Pielou均匀度指数(J')作为评价指标,其平均值为3.811、0.914和2.649,分析发现鱼类物种多样性呈减少趋势。对比历史资料发现,库区鱼类群落结构已发生改变,喜静水或缓流生境的鱼类逐渐成为库区优势种群;由于生态环境的改变,原河段流水型鱼类逐渐被替代,数量逐渐减少。  相似文献   

11.
海洋捕捞渔业是海洋经济的重要组成部分,同时也是海洋经济中具有代表性的高能耗产业之一。运用逐步回归分析方法,借助76份问卷调查数据,对长岛县2012年海洋捕捞渔船生产状况与燃油消耗进行了分析。结果表明,长岛县海洋捕捞渔业生产是全国海洋捕捞渔业发展现状的一个缩影,船龄老化、木质渔船为主、功率小型化特征突出以及船长、总吨指标偏小等特征与全国海洋捕捞渔船总体特征较为一致。模型拟合的结果显示,单船功率、总吨、渔获量以及作业方式对海洋捕捞燃油消耗具有显著影响,其中单船功率和渔获量指标的影响为正向。  相似文献   

12.
  1. The expansion and intensification of marine uses have severe cumulative impacts on marine ecosystems and human well-being, unless they are properly managed with an ecosystem-based management approach.
  2. A systematic conservation planning approach, using marxan with zones , was applied to generate alternative marine spatial plans for the Aegean Sea. Relevant human uses were included and their cumulative impact on a wide set of key biodiversity features was considered in the analysis. Different cost scenarios were developed to gain insight on the effects of the approaches used to assess socio-economic factors, and their potential impact on spatial plans.
  3. The spatial plans generated differed greatly depending on the method used to estimate opportunity costs and evaluate human activities in monetary terms.
  4. The vulnerability weights (the relative vulnerability of ecological features to specific human activities and their impacts) that were estimated based on a cumulative impact assessment, allowed the assessment of each zone in contributing to the achievement of conservation targets, through a transparent planning approach.
  5. Results indicate that special care should be given to how socio-economic activities, their impact on the ecosystems, and related costs are incorporated into planning.
  6. The proposed approach demonstrates how EU member states may effectively comply with the new Biodiversity Strategy 2030 targets, while planning for the sustainable use of their marine resources.
  相似文献   

13.
Climate change can impact the pattern of marine biodiversity through changes in species’ distributions. However, global studies on climate change impacts on ocean biodiversity have not been performed so far. Our paper aims to investigate the global patterns of such impacts by projecting the distributional ranges of a sample of 1066 exploited marine fish and invertebrates for 2050 using a newly developed dynamic bioclimate envelope model. Our projections show that climate change may lead to numerous local extinction in the sub‐polar regions, the tropics and semi‐enclosed seas. Simultaneously, species invasion is projected to be most intense in the Arctic and the Southern Ocean. Together, they result in dramatic species turnovers of over 60% of the present biodiversity, implying ecological disturbances that potentially disrupt ecosystem services. Our projections can be viewed as a set of hypothesis for future analytical and empirical studies.  相似文献   

14.
海鞘是主要海洋污损生物之一,对海洋生物多样性、海水养殖和生态环境都有不利影响。本文简述了中国东海几个主要水产养殖区7种海鞘优势种生物量、相关的次生代谢产物及其生物活性的研究进展,并对其利用前景进行了展望,为进一步研究开发提供依据。  相似文献   

15.
基于CART算法的长江口鱼种丰富度预测   总被引:1,自引:0,他引:1  
长江口是西太平洋最大的河口生态系统和典型的生态群落交错区,预测鱼类生物多样性对评价其生态系统有着重要的科学指示意义。结合2012―2013年长江口15个站点的渔业资源和环境调查数据,利用分类与回归树(CART)算法中的回归树算法,构建了长江口鱼种丰富度预测模型。基于1-SE准则,最优决策树的复杂性参数设置为0.067,结果表明,盐度、溶解氧和季节是影响长江口鱼类生物多样性的主要因子。此外,使用2014年的观测数据对回归树模型预测的长江口鱼种丰富度予以验证,均方根误差(RMSE)、平均相对误差(ARE)和平均绝对误差(AAE)值的统计结果显示,回归树模型在春、夏季的预测效能优于秋、冬季,模型总体上呈现出了较好的预测能力,表明利用CART算法对长江口鱼种丰富度进行预测是可行的。  相似文献   

16.
  • 1. Recent approaches to the planning of marine protected area (MPA) networks for biodiversity conservation often stress the need for a representative coverage of habitat types while aiming to minimize impacts on resource users. As typified by planning for the Australian South‐east Marine Region, this strategy can be manipulated by political processes, with consequent biased siting of MPAs. Networks thus created frequently possess relatively low value for biodiversity conservation, despite significant costs in establishment and maintenance.
  • 2. Such biases can be minimized through application of the data‐driven and species‐based concept of key biodiversity areas (KBAs).
  • 3. By mapping locations of threatened species and populations that are highly aggregated in time or space, the KBA process allows marine sites of global biodiversity significance to be systematically identified as priority conservation targets. Here, the value of KBAs for marine conservation planning is outlined, and guidelines and provisional criteria for their application provided.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

17.
Abstract  Catch composition, relative abundance and diversity of fish catches in open access and three old fisheries closures were compared and contrasted with previous ecological studies. There was less variation in catch community composition among the fishing grounds than the closures, suggesting that fishing has homogenised catch composition. The trap survey found that some parrotfish [ Leptoscarus vaigiensis (Quoy &Gaimard), Calotomus carolinus (Valenciennes) and Scarus ghobban Forsskål] were relatively more common and that some important predators of macro-invertebrates [ Balistapus undulatus (Mungo Park) and Cheilinus chlorourus (Bloch)] were less common in the fishing grounds than closures. Unexpectedly, and in contrast to visual census results, cumulative number of species in catch surveys was higher in open access than closures sites. This may result from fishers covering more area and habitat or a reduction in the catch of competitively subordinate and rare species by aggressive, early-caught fish that can dominate bait. Comparisons of ecological visual census surveys and fisheries-dependent methods indicated that small differences in catch composition can reflect larger ecological differences and that baiting methods can underestimate biodiversity. Ecological impacts of fishing and large-scale changes in marine ecosystems must be considerable given the many fisheries-dependent assessments report modest changes.  相似文献   

18.
19.
Climate change is projected to redistribute fisheries resources, resulting in tropical regions suffering decreases in seafood production. While sustainably managing marine ecosystems contributes to building climate resilience, these solutions require transformation of ocean governance. Recent studies and international initiatives suggest that conserving high seas biodiversity and fish stocks will have ecological and economic benefits; however, implications for seafood security under climate change have not been examined. Here, we apply global‐scale mechanistic species distribution models to 30 major straddling fish stocks to show that transforming high seas fisheries governance could increase resilience to climate change impacts. By closing the high seas to fishing or cooperatively managing its fisheries, we project that catches in exclusive economic zones (EEZs) would likely increase by around 10% by 2050 relative to 2000 under climate change (representative concentration pathway 4.5 and 8.5), compensating for the expected losses (around ?6%) from ‘business‐as‐usual’. Specifically, high seas closure increases the resilience of fish stocks, as indicated by a mean species abundance index, by 30% in EEZs. We suggest that improving high seas fisheries governance would increase the resilience of coastal countries to climate change.  相似文献   

20.
  1. The Government of Canada has committed to the Convention on Biological Diversity (CBD) Strategic Plan for Biodiversity, which includes the Aichi Biodiversity Targets.
  2. Aichi Target 11 indicates that countries are to conserve at least 10% of coastal and marine areas, especially areas of particular importance for biodiversity and ecosystem services, by 2020.
  3. In 2015 Canada affirmed its commitment to the 10% target, and also committed to an interim target to protect 5% of coastal and marine areas by the end of 2017. The interim target was met in October 2017 through a combination of federal and provincial marine protected areas (MPAs) and fisheries area closures that qualify as other effective area‐based conservation measures (OECMs), which are referred to domestically as marine refuges.
  4. In 2016 the Government of Canada set out a five‐point plan for achieving its marine conservation targets, which includes finishing what was started, protecting large offshore areas, protecting areas under pressure, advancing OECMs and establishing MPAs faster.
  5. Key challenges that the Government of Canada faces in meeting its 2020 marine conservation target include balancing socio‐economic impacts with the need to conserve biodiversity and sustain ecosystem health and ensuring meaningful engagement with partners and stakeholders in a short period of time.
  6. Once Canada has met its 2020 marine conservation target it will continue to advance ongoing marine conservation initiatives, most notably the development of a national conservation network, and seek to ensure effective long‐term conservation through the management, monitoring and enforcement of established MPAs and OECMs.
  相似文献   

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